Add support for updates from GitHub

Update/GitHubRelease.cs

@@ -0,0 +1,177 @@
+using Newtonsoft.Json;
+using Newtonsoft.Json.Converters;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+
+namespace Common.Update
+{
+    public partial class GitHubRelease
+    {
+        [JsonProperty("url")]
+        public string Url { get; set; }
+
+        [JsonProperty("assets_url")]
+        public string AssetsUrl { get; set; }
+
+        [JsonProperty("upload_url")]
+        public string UploadUrl { get; set; }
+
+        [JsonProperty("html_url")]
+        public string HtmlUrl { get; set; }
+
+        [JsonProperty("id")]
+        public long Id { get; set; }
+
+        [JsonProperty("tag_name")]
+        public string TagName { get; set; }
+
+        [JsonProperty("target_commitish")]
+        public string TargetCommitish { get; set; }
+
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        [JsonProperty("draft")]
+        public bool Draft { get; set; }
+
+        [JsonProperty("author")]
+        public Uploader Author { get; set; }
+
+        [JsonProperty("prerelease")]
+        public bool Prerelease { get; set; }
+
+        [JsonProperty("created_at")]
+        public DateTimeOffset CreatedAt { get; set; }
+
+        [JsonProperty("published_at")]
+        public DateTimeOffset PublishedAt { get; set; }
+
+        [JsonProperty("assets")]
+        public List<Asset> Assets { get; set; }
+
+        [JsonProperty("tarball_url")]
+        public string TarballUrl { get; set; }
+
+        [JsonProperty("zipball_url")]
+        public string ZipballUrl { get; set; }
+
+        [JsonProperty("body")]
+        public string Body { get; set; }
+    }
+
+    public class Asset
+    {
+        [JsonProperty("url")]
+        public string Url { get; set; }
+
+        [JsonProperty("id")]
+        public long Id { get; set; }
+
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        [JsonProperty("label")]
+        public string Label { get; set; }
+
+        [JsonProperty("uploader")]
+        public Uploader Uploader { get; set; }
+
+        [JsonProperty("content_type")]
+        public string ContentType { get; set; }
+
+        [JsonProperty("state")]
+        public string State { get; set; }
+
+        [JsonProperty("size")]
+        public long Size { get; set; }
+
+        [JsonProperty("download_count")]
+        public long DownloadCount { get; set; }
+
+        [JsonProperty("created_at")]
+        public DateTimeOffset CreatedAt { get; set; }
+
+        [JsonProperty("updated_at")]
+        public DateTimeOffset UpdatedAt { get; set; }
+
+        [JsonProperty("browser_download_url")]
+        public string BrowserDownloadUrl { get; set; }
+    }
+
+    public class Uploader
+    {
+        [JsonProperty("login")]
+        public string Login { get; set; }
+
+        [JsonProperty("id")]
+        public long Id { get; set; }
+
+        [JsonProperty("avatar_url")]
+        public string AvatarUrl { get; set; }
+
+        [JsonProperty("gravatar_id")]
+        public string GravatarId { get; set; }
+
+        [JsonProperty("url")]
+        public string Url { get; set; }
+
+        [JsonProperty("html_url")]
+        public string HtmlUrl { get; set; }
+
+        [JsonProperty("followers_url")]
+        public string FollowersUrl { get; set; }
+
+        [JsonProperty("following_url")]
+        public string FollowingUrl { get; set; }
+
+        [JsonProperty("gists_url")]
+        public string GistsUrl { get; set; }
+
+        [JsonProperty("starred_url")]
+        public string StarredUrl { get; set; }
+
+        [JsonProperty("subscriptions_url")]
+        public string SubscriptionsUrl { get; set; }
+
+        [JsonProperty("organizations_url")]
+        public string OrganizationsUrl { get; set; }
+
+        [JsonProperty("repos_url")]
+        public string ReposUrl { get; set; }
+
+        [JsonProperty("events_url")]
+        public string EventsUrl { get; set; }
+
+        [JsonProperty("received_events_url")]
+        public string ReceivedEventsUrl { get; set; }
+
+        [JsonProperty("type")]
+        public string Type { get; set; }
+
+        [JsonProperty("site_admin")]
+        public bool SiteAdmin { get; set; }
+    }
+
+    public partial class GitHubRelease
+    {
+        public static GitHubRelease FromJson(string json) => JsonConvert.DeserializeObject<GitHubRelease>(json, Converter.Settings);
+    }
+
+    public static class Serialize
+    {
+        public static string ToJson(this GitHubRelease self) => JsonConvert.SerializeObject(self, Converter.Settings);
+    }
+
+    internal class Converter
+    {
+        public static readonly JsonSerializerSettings Settings = new JsonSerializerSettings
+        {
+            MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
+            DateParseHandling = DateParseHandling.None,
+            Converters = {
+                new IsoDateTimeConverter { DateTimeStyles = DateTimeStyles.AssumeUniversal }
+            },
+        };
+    }
+}